1. Field of the Invention
The present invention relates to a gateway apparatus and information distribution system that can display various contents, including broadcasting contents from data center/broadcast station, on a viewer terminal via an IP network such as the Internet.
2. Description of Related Art
In recent years of a rapid spread of the broadband use in the Internet environment, such as XDSL and FTTH, a new generation of Internet services has began in which broadband services that provide rich contents, e.g., motion pictures, via Internet are utilized.
With the above background, there is an increasing need to distribute broadcasting contents to viewer terminals via an IP network. Unicast and multicast distributions are used as a video image distribution technology that distributes broadcasting contents to viewer terminals via the IP network. Unicast distribution is a video image distribution technology distributing broadcasting contents such as video images by performing a one-to-one communication between a terminal that can process communication based on an IP (hereafter referred to as “IP terminal”) and server that distributes the broadcasting contents on an IP network such as the Internet. Multicast distribution is a video image distribution technology that transmits contents having multicast addresses to the IP network, while individual routers copies and forwards data to downstream routers, each router serving as a turning point at a path from the server to an IP terminal, and an IP terminal receives the data of participating multicast address.
By employing the above-described video image distribution technology, it is possible to distribute broadcasting contents to IP terminals (viewer terminals) via the IP network.
In a general home/office setting, an IP terminal that can display video images is usually a personal computer. The display provided with such a personal computer is limited in screen size, because it is primarily used on a desktop. However, a TV apparatus in a home/office tends to have a larger screen, since its primary role is to view broadcasting video images, such as motion pictures. In reality, there are many homes and offices that have large-screen TV apparatuses.
However, many TV apparatuses that are already set in homes and offices do not have a function to receive data distributed via IP network. Therefore, in reality, only personal computers can display the broadcasting contents at home.
Although attempts have been made to provide TV apparatuses with IP terminal functions, consumers is required to buy new sets without making use out of the existing TV apparatuses, thereby largely financially burdening the user.